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全球范围内森林片断化现象日益严重。与其他木本植物(乔木和灌木)相比,木质藤本更趋向于分布在片断化森林的边缘,因而了解木质藤本对边缘效应的响应对于进一步了解其对森林动态的影响极其必要。本文对哀牢山中山湿性常绿阔叶林林缘到林内环境梯度上木质藤本的变化进行了调查。在形成年龄分别为13年、35年和53年的3种类型的林缘,设置从林缘向林内连续延伸的长方形样地(20 m×50 m)各10个(总面积3 ha),每个样地再划分为5个20 m×10 m的样方。在每个样方内对胸径≥0.2 cm且长度≥2.0 m的木质藤本进行了每木调查。在3 ha的林缘样地中共记录到木质藤本植物2,426株,隶属于14科19属31种。木质藤本的物种丰富度和多度均随距林缘距离的增加而降低,边缘效应深度在35年林缘的边缘为30 m,13和53年林缘的边缘则为20 m;它们的胸高断面积在53年林缘的边缘效应深度为20 m,但在13和35年林缘的不同距离上差异不显著。木质藤本对边缘效应的响应在物种水平上存在显著差异,主要呈现正向和中性的响应格局,包括只分布于林缘的物种,和从林缘到林内环境梯度上密度逐渐降低的物种;也有对边缘效应不敏感的物种。典范对应分析(CCA)表明,林冠开度、边缘形成年龄和土壤水分是决定木质藤本在片断化森林边缘分布的重要影响因子。
Global forest fragmentation is worsening. Compared to other woody plants (trees and shrubs), woody vines tend to be distributed on the edge of fragmented forests, and understanding the response of woody vines to edge effects is therefore essential for understanding their effects on forest dynamics. In this paper, the changes of woody vine on the forest environment gradient in the mid-mountain wet evergreen broad-leaved forest in Ailao Mountain were investigated. In the three types of forest margin of 13 years, 35 years and 53 years respectively, ten rectangular plots (20 m × 50 m) extending continuously from the forest margin to the forest were set up (total area 3 ha) Each plot is divided into five quadrats of 20 m × 10 m. Wood surveys were conducted on woody vines with DBH ≥0.2 cm and length ≥2.0 m in each quadrat. A total of 2,426 woody liana species were recorded in 3-ha forest samples, belonging to 31 genera and 19 genera in 14 families. The species richness and abundance of woody rattan decreased with the increase of the distance from the forest edge. The edge effect depth was 30 m at 35 years, and 20 m at 13 and 53 years. Their thorax height The edge effect depth of the forest margin with a cross-sectional area of 53 years was 20 m, but there was no significant difference in the distance between the 13 and 35 years. The responses of woody vines to edge effects were significantly different at the species level, showing mainly positive and negative response patterns, including those distributed only on forest margins and those with gradually decreasing densities from forest margins to the forest environment; There are also species that are insensitive to edge effects. Canonical correspondence analysis (CCA) shows that canopy opening, edge-forming age and soil moisture are the important factors that determine the distribution of woody vines on the edge of fragmented forest.